Born in New York City and raised in a working-class family in Greenwich Village, Breadon moved to St. Louis at the turn of the 20th century and entered the automobile industry by opening a repair garage. Moving into sales, he founded the Western Automobile Company, prospered as the owner of Pierce-Arrow dealerships and became a self-made millionaire. In 1917, he also became a minority investor – for $2,000 – in the Cardinals, then a struggling, second-division team chronically strapped for resources. But the club’s enterprising young president, Branch Rickey, discovered that the team could compete successfully against richer opponents by developing its playing talent on an assembly line of minor league teams, from Class D to Class AA (then the highest-ranking minor league level), that it owned and controlled. This was the creation of the farm system, perfected by the Cardinals and — when the Redbirds came to dominate the National League — copied by the 15 other MLB teams.

Rickey also served as manager of the Cardinals from 1919–25, and Breadon, who had bought out most of his partners to become majority owner, succeeded him as club president in 1920. In 1925, on May 31, Breadon moved Rickey into the front office full-time as business manager — general manager in contemporary terms — and promoted star second baseman Rogers Hornsby to playing manager.

The move was highly successful. Rickey would forge a Baseball Hall of Fame career as a general manager, while, in 1926, Hornsby’s Redbirds won the franchise’s first-ever National League pennant and World Series championship, a seven-game triumph over the New York Yankees of Babe Ruth and Lou Gehrig. But during the offseason, Breadon traded Hornsby to the New York Giants, the result of a heated confrontation between owner and player-manager in September 1926 over the playing of exhibition games during the September pennant race.

Under Breadon, the Cardinals ruled the baseball world in 1926, 1931, 1934, 1942, 1944 and 1946, and earned NL pennants in 1928, 1930 and 1943. In addition to Hornsby and Frisch, they would feature such standout players as Jim Bottomley, Chick Hafey, Dizzy Dean, Pepper Martin, Joe Medwick, Johnny Mize, Enos Slaughter, Marty Marion, Red Schoendienst, Stan Musial, Terry Moore, Harry Brecheen, Howie Pollet, Whitey Kurowski, Murry Dickson, and Walker and Mort Cooper.

Rickey worked for Breadon until the end of 1942 and enjoyed wide-ranging authority, but Breadon always reserved the right to choose the team’s field manager. In addition to Hornsby, he would select men such as Bill McKechnie, Billy Southworth, Gabby Street, Frankie Frisch (obtained from the Giants in the Hornsby trade) and Eddie Dyer to run the Cardinals’ bench. All save McKechnie, the Cards’ losing skipper in the 1928 World Series, won world championships for St. Louis, although he would be elected to the Baseball Hall of Fame in 1962 for his credentials as a manager. (Hornsby and Frisch were elected to the Hall of Fame on the strength of their brilliant playing careers, and in 2008 Southworth would enter the Hall posthumously for his managerial success.)

Despite their success on the field, the 1931–1945 Cardinals were frequently plagued by low attendance. Although they were by far the dominant team, they shared St. Louis, the smallest, two-team market in the major leagues, with the American League Browns. Their home attendance also was devastated by the Great Depression, with the 1934 world champions—the colorful “Gashouse Gang”, one of the most memorable teams in MLB history—drawing only 325,000 fans. Breadon seriously explored selling the team in 1934; then, after his Cardinals had defeated the Detroit Tigers in that year’s World Series, Breadon, with his connections within the auto industry, openly pondered moving the Redbirds to Detroit.

Both ideas came to nothing, however; the team remained in St. Louis and continued to struggle at the turnstiles, drawing only 291,000 fans in 1938 during a rare losing season, and not reaching pre-Depression attendance levels until the pennant-contending 1941 edition. But World War II interrupted the momentum and — despite their three pennants and two World Series titles — the Cardinals treaded water in attendance, although exceeding the National League average, from 1942–1945. However, with their on-field success and the advent of radio in the 1930s, they would develop a fanatical regional following, their appeal extending beyond Missouri and throughout the lower Midwest, Arkansas, Louisiana, the Great Plains states and much of the Southwest.

Attendance was about to spike in 1946 with another championship team and the postwar baseball boom, but the Cardinals maintained their reputation for a tight-fisted control on player salaries.

In June 1946, Breadon flew to Mexico City — without the permission of Commissioner of Baseball Happy Chandler and National League president Ford Frick — for a “fact-finding” meeting with Pasquel; the raids on the Cardinals stopped, but Breadon was hit with a $5,000 fine and a 30-day suspension by Chandler, although both punishments were quickly rescinded. Lanier, Klein and Martin, meanwhile, were banned by Chandler from Organized Baseball for jumping their contracts; they would not be reinstated until June 5, 1949.

Then, in 1947, Breadon learned that some of his players planned to strike rather than take the field against Jackie Robinson of Rickey’s Dodgers, the first African-American to play Major League Baseball since the 1880s. The idea of a strike had originated with Robinson’s disaffected teammate, Dixie Walker, but it had sympathizers across the league and widespread support among the Cardinals. Breadon flew to New York, conferred with NL president Frick, and then met with his team, where he read a strongly worded message from Frick vowing to suspend all the strikers from baseball. The threat then evaporated.

Breadon died in St. Louis 18 months later at the age of 72. As it turned out, the ballpark fund nearly forced the Cardinals out of town. When the tax dodge that made the purchase possible came to light, Saigh—who by this time was sole owner—was forced to put the Cardinals on the market. Just as it appeared they were moving to Houston, Texas, Anheuser-Busch and its president, Gussie Busch, stepped in to buy the team in 1953 and keep it in St. Louis.